Double-shell vaporizer



FIG. 1 is a top, front and right side perspective view of a vaporizer showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines in the drawings illustrate portions of the vaporizer which form no part of the claimed design.

The oblique shade lines in the drawings represent a transparent surface. 

CLAIM The ornamental design for a vaporizer, as shown and described. 